This invention relates generally to a carding machine and more particularly to a device for adjusting the position of a taker-in under casing relative to one or both of a taker-in roller and a dish plate in the carding machine.
As is well known, it is one of main functions of a taker-in under casing to carry out separation of impurities, which are unworthy of being used for spinning, from a satisfactory fiber material. The separation is effected in a manner that the satisfactory fiber material, which is easily gripped by a taker-in roller provided with a fiber-gripping surface, for example in the form of a Garnett wire, is allowed to pass through between the taker-in roller and the taker-in under casing along with a resulting stream of air whereas the impurities, such as dirt having a relatively large terminal speed sufficient to overcome the function of the resulting air stream, and short fibers which are too short to be gripped by the taker-in roller, and thrown out of the taker-in roller and dropped through the taker-in under casing. It is possible to control both the quantity and a quality of impurities to be removed at the taker-in under casing by adjusting both or either of the spacing between the downstream end of the dish plate and the upstream end of the taker-in under casing and the gauge between the taker-in roller surface and the taker-in under casing at the upstream end thereof.
Heretofore, the following proposals have been provided to bring about a desired separation of impurities at the taker-in under casing:
1. To vary the leading gauge between the taker-in roller and the taker-in under casing. PA1 2. To replace the taker-in under casing with one having a different length. PA1 3. To adjust the position of a mote knife, that is to vary the gauge between the mote knife and the taker-in roller.
With respect to the proposal (1), since the prior taker-in under casing is mounted on a machine frame in an unadjustable manner, the taker-in under casing has to be disadvantageously removed from the machine frame whenever practising the proposal. As readily understood, such a disadvantage is also present for the proposal (2). In addition, in the case of the proposal (3), the mote knife may cause an undesirable stream of air to be created particularly when it is applied to a high speed card and this proposal is therefore not only unsuitable for the high speed card, but lacking in reliability of its ability to separate impurities.
Thus, it is understood that all of the prior proposals require complicated and skilled adjusting operation of the taker-in under casing or the mote knife and therefore they are not satisfactory.